• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
5-Volt Reference | B1395 02 | B1395 05 | B1395 05 | -- |
Memory Seat Sensor Low Reference | -- | B1825 01, B1850 01, B1860 01, B2355 01, B2365 01, B2375 01 | -- | -- |
Driver Seat Front Vertical Position Sensor Signal | B2355 06 | B2355 06 | B2355 01 | -- |
Driver Seat Rear Vertical Position Sensor Signal | B2365 06 | B2365 06 | B2365 01 | -- |
Driver Seat Horizontal Position Sensor Signal | B2375 06 | B2375 06 | B2375 01 | -- |
Driver Seat Lumbar Vertical Position Sensor Signal | B1860 06 | B1860 06 | B1860 01 | -- |
Driver Seat Lumbar Horizontal Position Sensor Signal | B1850 06 | B1850 06 | B1850 01 | -- |
Driver Seat Recline Position Sensor Signal | B1825 06 | B1825 06 | B1825 01 | -- |
The memory seat module (MSM) supplies a 5-volt reference voltage to the driver seat and adjustable pedal position sensors. The MSM monitors this reference voltage to ensure the accuracy of the voltages being returned from the sensors. If the voltage exceeds the normal operating range, errors will occur in the memory recall operations of the seat and adjustable pedals.
The memory seat module must be powered.
The following conditions exist for more than 1 second:
The reference voltage drops below 4.75 volts.
The reference voltage exceeds 5.15 volts.
All memory recall functions will be disabled.
• | The current DTC will clear 3 seconds after the reference voltage returns to normal operating range, and the ignition is cycled OFF then back to ACC or RUN. |
• | A history DTC will clear after 50 ignition cycles or with a scan tool using the clear DTCs function. |
An internal short to ground in one of the position sensors may set this DTC.
Ignition ON, test for 4.75-5.15 volts between the 5-volt reference circuit and ground.
⇒ | If less than 4.75 volts, test the 5-volt reference circuit to all position sensors for a short to ground or an open. If the circuit tests normal, replace the memory seat module. |
⇒ | If greater than 5.15 volts, test the 5-volt reference circuit to all position sensors or a short to voltage. If the circuit tests normal, replace the memory seat module. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for MSM replacement, setup, and programming |